A common injury is the accidental introduction of foreign material into an eye. To date, the techniques for treating such an injury have various drawbacks. The most common form of treatment is an improvised method which consists of administering a liquid eyewash over the external surface of the eye by squirting an eyewash through a tube which extends from a bag of treatment solution. This method requires the person administering the eyewash to immobilize the eyelids with one hand, while holding the end of the tube with the other, and sweeping the eyewash across the eye until the entire surface of the eye is washed properly.
There are several disadvantages to this method. One disadvantage is that a patient tends to feel threatened by it. For an eye to be properly washed by the above method, it is generally required that the patient lie motionless in a recumbent position. It is difficult for the patient to do this when he is aware that he is about to undergo a rather uncomfortable process, i.e. having a fluid squirted into an eye. The eye is a sensitive organ and it is a natural reaction for the patient to try to protect the eye by either closing it or averting his head. The patient thus feels threatened by the above method, making it harder for him to remain motionless, with the resultant effect of making the eyewashing process more difficult.
Another disadvantage is that the technique described above requires an experienced person to administer the eyewash. This will usually be a medical person whose uninterrupted attention is required for eyewashing, making it impossible for him or her to treat other related injuries which possibly resulted from the same accident.
A further disadvantage is that drainage of the eyewash from the eye cannot be controlled. The eyewash can flow onto the face and clothing of the patient, and onto surrounding areas.
There are other, more innovative ways of treating an eye, such as the scleral lens disclosed in U.S. Pat. No. Re. 28,873, granted June 22, 1976 to Lorne B. Morgan. The lens employs a cup-like eye shield having a concave inner surface which overlies the front portion of the eye. However, the lens has many of the same drawbacks which were described above. For example, the lens must be used by a professionally trained individual. In addition, the lens does not enable the eye to be open while the lens is in use. Also, the system provides no way of controlling the drainage of the eyewash from the eye. Goggle type eyewashing devices are known. It is also known to use an eyecup placed over an eye as a method of confining an eyewash in a chamber for contacting the eye. It is also known to use tubing for delivering and draining eyewash to and from the chamber formed by the eyecup.
Prior art devices which are pertinent to the present invention are disclosed by the following United States patents:
U.S. Pat. No. 676,379, granted June 11, 1901 to Frank E. Young; No. 1,006,945, granted Oct. 24, 1911 to James D Houston; No. 1,246,971, granted Nov. 20, 1917 to Friedrich Maier; No. 1,362,682, granted Dec. 21, 1920 to Frank E. Dayton; No. 1,437,435, granted Dec. 5, 1922 to Friedrich Maier; No. 1,900,201, granted Mar. 7, 1933 to Solomon M. Sager; No. 2,524,720, granted July 24, 1946 to Charles A. Watrous; No. 2,818,068, granted Sept. 2, 1955 to Anthony De Felice; No. 3,261,355, granted Mar. 11, 1964 to Henry Burbig; No. 3,664,340, granted May 23, 1972 to Loran B. Morgan; No. 4,193,401, granted Mar. 18, 1980 to Rosolino Marinello; and U.S. Pat. No. Re. 28,873, granted June 22, 1976 to Loran B. Morgan.
Particularly pertinent to the present invention is Maier, U.S. Pat. No. 1,437,435. Although this patent, and the other above-cited patents, address some of the above discussed disadvantages to varying degrees, they fail to address a major problem associated with washing an eye.
When washing an eye, it is important to keep the eye open so that the eyewash contacts and covers as much surface of the eye as is possible. However, keeping the eye open is counter to the natural reaction a person has to close the eye when a foreign object or substance is introduced into it. Such a reaction is primarily involuntary because of the high sensitivity of the eye to contact.
The cornea region of the eye is particularly sensitive to contact. When the cornea is contacted by a foreign object or substance, such as for example, particles or dust or other particulate matter, a corneal reflex is induced causing a blepharal spasm. A blepharal spasm is a strong involuntary muscular reaction by the eye which reflexively closes the eye in response to the introduction of a foreign substance. It is not necessary that a particle contact the cornea region to induce a blepharal spasm. For example, applying eye drops to an eye directly on the pupil or iris can induce a blepharal spasm. Or, applying an eyewash by using one eyecup can also induce a blepharal spasm if the eyewash is applied improperly.
Therefore, for an eyecup to be effective in a method for washing an eye, it is desirable that it have two features. First, the eyecup should have the capability to hold the eye open while it is being washed. Second, the eyewash should be delivered into the chamber formed by the eyecup such that the eyewash does not induce a blepharal spasm. It is believed that none of the above-cited patents provide devices or methods which provide these two features.
The advantages of the present invention over the patents cited above will become apparent upon further reading of this application.